Penicillin - the world's first "wonder drug" - was discovered, more-or-less by accident, by Scottish scientist Alexander Fleming in 1928. But Dr. Fleming was unable to harness the natural bacteria killer and turn it into a useful medicine. It wasn't until the 1940s that a team at Oxford University led by Howard Florey succeeded where Dr. Fleming had failed. Their work is the subject of a recent book, "The Mold in Dr. Florey's Coat."

One thing that changed between Fleming's failure and Florey's success, says Eric Lax, was the way science was practiced in Britain. In the late 1920s, Alexander Fleming worked pretty much alone. But in the years that followed, the value of scientific teamwork was recognized. "When Fleming was doing his work in 1928, he was really a lone bacteriologist in his lab, running experiments. And biochemistry was just coming into its own. And it was really the work of Howard Florey, who was the professor of pathology at Oxford, who put together the group that developed penicillin into a drug, who understood that for science to move forward, it had to be interdisciplinary, that he needed a chemist, he needed a biochemist, he needed a variety of people who could bring their own intelligence to bear on a problem, and then they could take it apart to its small bits and then try to solve it upward from there," he says.

The team included Dr. Florey, an Australian; Ernst Chain, a German-Jewish refuge; and Englishman Norman Heatley.

Alexander Fleming was an acclaimed scientist who was stumped by the penicillin problem. So I wondered what drove Dr. Florey to persevere where Fleming and others had failed. "He was somebody who was intrigued by a problem, and penicillin [and] the whole notion of antibiotics, of naturally-occurring antibiotics, was something that was part of a larger interest that he had throughout his career. He spent the bulk of his career, after penicillin and before, dealing with mucus, which sounds like a funny thing to be doing, but when you realize how important a part it plays in our own health, it provides a barrier of defense against some bacterial infections that come in, it's a great sort of natural protection that we have - so the notion of natural protection was something that was very interesting to him," says Mr. Lax.

Eric Lax isn't known as a science writer; he is probably best-known, in fact, as the biographer of filmmaker Woody Allen. He first became interested in the penicillin story when he read the obituary of an American woman who died in 1999. She led a rather unremarkable life except that in 1942, Anne Miller was reportedly the first person whose life was saved by penicillin. "The more I looked into it, the more fascinated I became by it," he says. "One of the great things about this story is, it's such a human story. It's people working on a shoestring budget. There are personality rivalries. There's great science that's done. And then there's this tremendous backdrop of World War II that's going on behind it as this is being done."

In those days, combat infections were a deadly killer - half of the battlefield deaths in World War I were attributed to infections. But even though their research was being done at the height of World War II, Dr. Florey and his Oxford colleagues worked on a very limited budget. Their first grant request for 100 pounds was knocked down to just 25.

To this day, Alexander Fleming remains the name most closely associated with the development of penicillin. There are a number of possible reasons for that. Dr. Fleming had a strong supporter in Lord Beaverbrook, the British press baron. Florey and his Oxford colleagues were more circumspect. "Self-promotion was completely frowned upon. You could really be thrown out of the medical profession for that. While Florey and his colleagues didn't mind if nobody got credit for all this, they certainly chafed when they found that Fleming was getting an enormous amount and nobody was really looking at the work they had done," says Mr. Lax.

Dr. Fleming, meanwhile, kept a scrapbook of all the published stories that misattributed his role in the development of the wonder drug. He was said to be amused by it, but didn't do much to correct the historical record.

In the end, Alexander Fleming shared the 1945 Nobel Prize with Howard Florey and his Oxford colleague, Ernst Chain. But they didn't get rich. "No, not at all. They made no money whatsoever on penicillin. What they did, if course, get was the tremendous satisfaction of having changed the world," says Mr. Lax.

Eric Lax is the author of The Mold in Dr. Florey's Coat, published by Henry Holt. Oh, and about that title? Doing their research during World War II, when the war was not going very well at all for Britain, the researchers feared having to abandon their work in Oxford and flee ahead of a German invasion of England. So they rubbed hearty penicillin spores into their clothes so they would have the raw material in case they had to take up their work somewhere else.